Telephone-meter.



Patented Dec. 3|, I90l.

H. A. HOLDREGE.

V TELEPHONE METER.

(Appiication filed June 3, 1901.)

(No Model.)

' INVENTOR.

B2: 7 T v M W.

TTORNEXS WITNESSES 4 UNITED STATES PATENT OFFICE.

HENRY A. HOLDREGE, or CHIC-AGO, ILLINOIS.

TELEPHONE-METER.

SPECIFICATION forming part of Letters Patent No. 690,289, dated December31, 1901.

Application filed June 3. 1901.

To all whom it may concern:

Be it known that I, HENRY A. YHOLDREGE, a citizen of the United States,residing in Ohicago, in the county of Cook and State ofIllinois,haveinvented anew and useful Improve- The prime object of theinvention is to socontrive the electrical devices and circuits that anindividual subscriber may call the central office for a connection inthe usual manner, he answered by the central oflice, and the usualattemptbe made at the central office to secure the desired connectionwithout operating the register, which latter is not operated until thecalled subscriber has been put in connection with the calling subscriberand not then until the connection thus made has been broken by the actof the operator at the central office in removing the answering-plu g.The arrangement is such that only the first step toward the operationofthe registering device is taken when the connection between the twosubscribers is completed, the registration itself being completed onlywhen that connection is broken. This is accomplished by means of apolarized relay operating in connection with each of the electromagneticregisters (one for each subscriber) and a reversing-relay in each of thecord-circuits at the central office in conjunction with the usualcircuits and instruments now commonlyin use, and herein consists theinvention, generally stated.

The accompanying drawing, which forms a part of this specification,shows in diagramlnatic form the invention in connection with a centralstation and two subscribers telephones.

In said drawing, A represents what we may suppose to be acalling-subscribers telephone and the electrical and mechanicalapparatus there situated.

B,in like manner, represents what may be supposed to be the telephone ofthe called subscriber.

All the other circuits and apparatus shown Serial No. 62,878. on, 510111.)

on the diagram may be supposed to be located at the central station. 1

In order to distinguish more clearly the devices and parts and circuitswhich are now commonly in use from those which have been changed oradded in furtherance of the presentinvention, the latter have beenmarked upon the diagram in dotted lines, while the former or' old partsand circuits are shown in full lines. With reference to the well-knownparts shown in the diagram it will be sufficient to state that arepresents the callingsubscribers transmitter; a, his receiver; a hiscall'bell; a his condenser, and a a the two parts of his line-wire,while I), 6, b b b and b are corresponding parts of thereceiving-subscribers apparatus, and in like manner at the centralstation 0 is the operators transmitter; c, the operators receiver; 0 theringing-generator, and c the operators condenser.

D is the usual ringing-switch; D, the usual listening-switch; E and E,the usual supervisory relays; F, the repeating-coil; G G, thecall-signal lights; H H, the supervisory-signal lights; J, theanswering-plug, and J the connecting-plug.

K K are the answering-jacks for receiving the answering-plug, and-L L"are the connecting-jacks for receiving the connecting-plug.

M M are the cut-elf relays, and N N the call-relays.

O is the battery.

Thus far described the apparatus is precisely such as is in common andgeneral use in many telephone systems now in operation.

Referring now to the parts which have 'been added and which are shown indotted lines, P is a reversing-relaythat is to say, an electromagnetwhich when energized operates a switch or switches in such manner as toreverse the direction of the current through the line controlled by saidswitch or switches,

Q is a polarized relay, the current through which is controlled by thereversing-relay above mentioned.

R is the registering-magnet, the armature R of which is connected to themechanism of the register S.

T is an extra contact-point at the cut-off relay for closing the circuitthrough the registering-magnet R when the cut-off relay is energized.

U is a contact device for the armature R- of the register-magnet, whichis closed when the register-magnet is energizedand the register operatedfor cutting out the operation of the polarized relay.

The operation of the circuit and apparatus is as follows: Suppose thesubscriber at sta tion A removes his receiver from its hook and by thatact closes the circuit through his main line to the central oiiice. Thecircuit will then pass through the call-relay N, which will close thecircuit through the call-signal light G, whereby the operator at thecentral office is warned of the call. The central operator will theninsert the answering-plug J into the answering-jack K, which energizesthe cut-off relay M and by causing the movement in its armature closescontact'at the contact-point T.- At the same time and by the same energythe cut-off relay disconnects in the usual manner, as will be seen, thecircuit to the call-signal light G. The central operator is now inposition to talk to the calling subscriber, as will be readilyunderstood,

and, having ascertained, for example, that a connection withthesubscriber B is required, inserts the connecting-plug J in theconnectinggi'aek L, and at the same time closes the ringing switch D,which signals the subscriber B by ringing his bell; Now when thesubscriber B takes down his telephone, and thus closes his circuit, shunting his condenser b the effect is to energize the supervisory relay E,and thus close the circuit through the reversing-relay P, which reversesthe circuit through the polarized relayQand causes it to swing itsarmature and close contact at contact-point q, whereby the circuit isclosed through the register-magnet R, and its armature R is thusbroughtinto contact with the contact-point U, so that the circuit willbe maintained through the register-magnet R thereafter, even though itshall be broken through the polarized relay, and will continue thus solong as the contact remains unbroken at the contact-point T. This isimportant, because it may happen that the operator at the centralstation or the subscriber at either of the subscribers stations maybreak the circuit by moving the telephone-hook or by the centraloperator at thecentral station by removing the connectingplug J, any ofwhich things may be done in this arrangement and under suchcircumstances without deenergizing the registermagnet R. However, whenthe subscribers are through talking and one or both of their receiversare hung up and their circuit'thus broken and the central operatorfinally removes the answering-plug J the contact at the contact-point Tis thus broken and the register-magnet R thus thrown out of circuitcompletely or denergized, and the armaturespring 3 then comes intoaction and withdraws the armature R, to which is connected the rod 3',which enters the register S and operates the same mechanically to movethe register-wheels, and thus register an additional number or unit. Itwill not be necessary to describe the, mechanism inclosed in theregister, as any well-known counting mechanism operated by a singlemechanical impulse may i be employed. 7

From the foregoing it will be seen that each complete connection had byany one sub scriber with anyother is automatically registered withoutany special or unusual action of either the calling or called subscriberbeing required and that this takes place only after the connection hasbeen completely made at .the centraloffice'and finally broken at thecentral office, and, moreover, requires no special manipulation on thepart of the operator at the central office beyond the usualmanipulations now required, and, furthermore, in no way interferes withthe operation of the usual signaling devices now commonly employed, so,that the register will indicate, and only indicate, completed callswhere the calling and called subscribers have been in actualcommunication, and such registration cannot be produced or brought aboutby any act'of the subscriber or subscribers alone nor by any act of theoperator at the central office alone, but requires the joint action ofthe operator at the central oiiice and two subscribers, so that perfectassurance is given that the register will indicate automatically exactlywhat is desired shall be registered, and all of this without any specialmanipulation on the part of the subscriber or of the central operator,and all of this, too, notwithstanding any attempt that may be made byeither subscriber or operator, to signal each other or the centraloffice by manipulating the telephone-hook.

In the central upper portion of the diagram three unletteredresistance-coils are shown. This is an old device already in use inconjunction with supervisory-signal lights, such as H and H, which havebeen heretofore used in a similar relation. Such signal-lights arecommonly constructed to burn on a difierence of potential of twelvevolts. The battery of the exchange is ordinarily constructed to supplyabout twice that voltage. Now the two upper unlettered resistance-coilsin the diagram are connected, it will be seen, in series with the lamps,and thus deliver the proper current to the signal-lights when saidsignallights are burning. Now when -the supervisory relay E is energizedand its armature drawn up the lowermost one of the three unletteredresistance -coils is brought into a shunt-circuit around the lamp H, sothat a portion of the current to said lamp is thereby diverted from saidlamp and the lamp thereby dimmed or nearly extinguished. The coil on thereversing-relay P serves as a similar resistance for dimming thesignal-lamp H when the supervisory relay E is energized. The generalpurpose of this arrangement is to enable the operation of the two signallights after the plugs J or J are inserted in their respective jackswithout breaking the circuit through said plugs-in other words,

to enable the operation of the signal-lights as required and at thesametime maintain the circuit through the plugs. I do not claim to haveinvented this arrangement, which is a well-known one, but merely insertthis description so that the construction illustrated in the diagrammaybe understood.

I claim- 1. In a telephone system consisting of a central office and twoor more subscribers telephone-stations, the combination with the in-.

struments and circuits thereof, of a mechanical registering device, aregister-magnet for operating the same, a polarized relay which controlsthe register-magnet, and a reversingrelay which controls the polarizedrelay, subtral office and two or more subscribers telephone-stations,the combination with the instruments and circuits thereof, of amechanical registering device, a register-magnet for operating the same,a polarized relay which controls the register-magnet, a reversing-relaywhich controls the polarized relay, anda circuit closed by the armatureof the registermagnet, whereby after said register-magnet has acted areversal or interruption of the circuit through the polarized relaycannot break the circuit through the register-magnet, substantially asspecified.

4. In a telephone system consisting of a central office and two or moresubscribers tele phone-stations, the combination with theinstruments'and circuits thereof, of a mechanical registering device, aregister-magnet for operating the same, a polarized relay which controlsthe register-magnet, a reversing-relay which controls the polarizedrelay, and a switch in the line to the register-magnet, as for examplethe armature of the cut-off relay, which magnetis controlled by theansweringplug of the central operator, whereby the removal of saidanswering plug will break the circuit throughthe register-magnet andpermit the registration to take place, substantially as specified.

H. M. MUNDAY EDWARD S. EVARTS.

